Teleflex TFX320 Operation Manual page 9

The RTS window plots the depth and intensity of a sonar return. Sonar intensity
is indicated by the length of the horizontal lines, while depth is indicated by the
vertical placement of the lines next to the depth range scale. The intensity of
the sonar return is divided into 16 levels of grayscale. The most intense returns
are shown in black; less intense sonar returns are shown
in progressively lighter shades of gray.
The combination of the length of the lines and the
grayscale level helps to identify the bottom composition
and structure. The bottom is the largest grouping of
black horizontal lines, typically having gray lines
underneath. A harder bottom shows less gray below; a
soft bottom shows more gray below. Structure appears
above the bottom as a cluster of lines with varying
lengths and gray shades.
Fish appear as smaller groupings of sonar returns
between the bottom and surface. Often, large fish
within structure will show as a strong return within a
grouping of smaller returns. When the boat is stationary
or drifting very slowly, the RTS window can show the
movement of the fish through the transducer beam.
Moving fish appear as smaller groups of lines
progressively become larger lines, or vice . A grouping of
lines moving vertically indicates a fish changing depth.
The width of the RTS window can be adjusted to your
preference. Selecting a wider RTS window shows
greater differences between the strength of the sonar
returns; however it reduces the amount of history on
the display. See Control Panels for details of adjusting
the RTS Window.
USING THE 320 SERIES
CONTROL FUNCTIONS
Hard
Bottom
Fish
Soft
Bottom
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